# encoding: utf-8
module TaxCloud #:nodoc:
  module Errors #:nodoc:
    # Default parent TaxCloud error for all custom errors. This handles the base
    # key for the translations and provides the convenience method for
    # translating the messages.
    #
    # Generously borrowed from Mongoid[https://github.com/mongoid/mongoid/blob/master/lib/mongoid/errors/mongoid_error.rb].
    class TaxCloudError < StandardError
      # Problem occurred.
      attr_reader :problem

      # Summary of the problem.
      attr_reader :summary

      # Suggested problem resolution.
      attr_reader :resolution

      # Compose the message.
      # === Parameters
      # [key] Lookup key in the translation table.
      # [attributes] The objects to pass to create the message.
      def compose_message(key, attributes = {})
        @problem = create_problem(key, attributes)
        @summary = create_summary(key, attributes)
        @resolution = create_resolution(key, attributes)

        "\nProblem:\n  #{@problem}" \
        "\nSummary:\n  #{@summary}" \
        "\nResolution:\n  #{@resolution}"
      end

      private

      BASE_KEY = 'taxcloud.errors.messages' #:nodoc:

      # Given the key of the specific error and the options hash, translate the
      # message.
      #
      # === Parameters
      # [key] The key of the error in the locales.
      # [options] The objects to pass to create the message.
      #
      # Returns a localized error message string.
      def translate(key, options)
        ::I18n.translate("#{BASE_KEY}.#{key}", { locale: :en }.merge(options)).strip
      end

      # Create the problem.
      #
      # === Parameters
      # [key] The error key.
      # [attributes] The attributes to interpolate.
      #
      # Returns the problem.
      def create_problem(key, attributes)
        translate("#{key}.message", attributes)
      end

      # Create the summary.
      #
      # === Parameters
      # [key] The error key.
      # [attributes] The attributes to interpolate.
      #
      # Returns the summary.
      def create_summary(key, attributes)
        translate("#{key}.summary", attributes)
      end

      # Create the resolution.
      #
      # === Parameters
      # [key] The error key.
      # [attributes] The attributes to interpolate.
      #
      # Returns the resolution.
      def create_resolution(key, attributes)
        translate("#{key}.resolution", attributes)
      end
    end
  end
end
